Tunable Exceptional Points for Quantum Sensing in a Spin--Orbit-Angular-Momentum Coupled BEC

• URL: http://arxiv.org/abs/2608.31095v1
• Date: Mon, 31 Aug 2026 17:03:30 GMT
• Title: Tunable Exceptional Points for Quantum Sensing in a Spin--Orbit-Angular-Momentum Coupled BEC
• Abstract summary: We investigate a tunable EP sensing platform based on the intrinsic non-Hermitian Bogoliubov dynamics of a Bose-Einstein condensate.<n>We identify multiple EPs and map their trajectories, revealing strong quantum Fisher information enhancement when the EPs are approached from the PT-symmetric stable regime.<n>We show that a spin-density measurement can approach the quantum Fisher information limit, providing an experimentally accessible route to tunable EP-enhanced quantum sensing in Bose-Einstein condensates.
• Score: 31.056304866140625
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Exceptional points (EPs) can induce strongly amplified responses to weak perturbations, but enhanced spectral sensitivity in conventional non-Hermitian systems does not necessarily translate into improved quantum-limited sensing because of the associated gain and loss noise. Here, we investigate a tunable EP sensing platform based on the intrinsic non-Hermitian Bogoliubov dynamics of a spin-orbit-angular-momentum-coupled Bose-Einstein condensate. Starting from a fully Hermitian microscopic Hamiltonian, we derive a Bogoliubov dynamical matrix that exhibits parity-time (PT) symmetry, with EPs tunable through the Raman coupling and interaction parameters. We identify multiple EPs and map their trajectories and associated stability landscapes, revealing strong quantum Fisher information enhancement when the EPs are approached from the PT-symmetric stable regime. We further find that the gap-opening rate around a second-order EP provides a useful relative indicator for comparing the sensing performance of EPs, while higher-order EPs are not necessarily accessible from the stable regime. Moreover, two second-order EPs can be tuned to overlap, allowing their sensing contributions to add and yielding a linear enhancement of the total quantum Fisher information. Finally, we show that a spin-density measurement can approach the quantum Fisher information limit, providing an experimentally accessible route to tunable EP-enhanced quantum sensing in Bose-Einstein condensates.

Related papers

• Testing the weak equivalence principle for nonclassical matter with torsion balances [41.99844472131922]
  We propose tests of the weak equivalence principle (WEP) using a torsion balance.<n>We derive a model to derive the matrix elements of the free-fall operator.<n>We demonstrate how the validity of the WEP may be tested in a torsion balance setup.
  arXiv  Detail & Related papers  (2025-12-06T07:44:00Z)
• Quantum sensing of displacements with stabilized GKP states [41.94295877935867]
  We show how protocols for the stabilization of Gottesman-Kitaev-Preskill states can be used for the estimation of two-quadrature displacement sensing.<n>Thanks to the stabilization, this sensor is backaction evading and can function continuously without reset, making it well suited for the detection of itinerant signals.
  arXiv  Detail & Related papers  (2025-06-25T17:18:50Z)
• Unification of Exceptional Points and Transmission Peak Degeneracies in a Highly Tunable Magnon-Photon Dimer [41.94295877935867]
  This work presents a microwave magnon-photon dimer with near-universal tunability across all relevant parameters.<n>We show that two-dimensional EP and TPD configurations can be unified into a general theory and experimental framework.<n>Our formalism and experimental methods unify previous EP and TPD configurations and may lead to the realization of robust TPD-enhanced sensors.
  arXiv  Detail & Related papers  (2025-06-10T18:01:01Z)
• Higher-order exceptional points in a non-reciprocal waveguide beam splitter [1.5845117761091052]
  We analytically derive eigenvalues and numerically demonstrate the formation of exceptional points (EPs) in non-Hermitian systems.<n>Our results open new pathways for realizing higher-order EPs in non-reciprocal open quantum systems.
  arXiv  Detail & Related papers  (2025-03-27T12:38:58Z)
• Topological transitions in quantum jump dynamics: Hidden exceptional points [45.58759752275849]
  Phenomena associated with exceptional points (EPs) and their applications have been extensively studied.<n>We consider a monitored three level system and find multiple EPs in the Lindbladian eigenvalues considered as functions of a counting field.<n>We demonstrate that these EPs signify transitions between different topological classes.
  arXiv  Detail & Related papers  (2024-08-09T18:00:02Z)
• Multitype entanglement dynamics induced by exceptional points [9.033507137659411]
  We study a generic model composed of two coupled non-Hermitian qubits.<n>The diverse entanglement dynamics on the two sides of the original fourth-order EP (EP4') and second order EP (EP2) can be observed simultaneously.<n>Our study paves the way for the investigation of EP-induced quantum effects and applications of EP-related quantum technologies.
  arXiv  Detail & Related papers  (2024-06-23T04:46:02Z)
• Scaling of quantum Fisher information for quantum exceptional point sensors [18.33055905849827]
  In recent years, significant progress has been made in utilizing the divergence of spectrum response rate at the exceptional point (EP) for sensing in classical systems. For a quantum EP sensor, an important issue is the relation between the order of the quantum EP and the scaling of quantum Fisher information (QFI)
  arXiv  Detail & Related papers  (2024-04-04T20:47:54Z)
• Parity-time-symmetric two-qubit system: entanglement and sensing [0.0]
  We study exceptional-point effects and quantum sensing in a parity-time (PT)-symmetric two-qubit system with the Ising-type interaction. We show that entanglement can be generated more quickly than the corresponding Hermitian system.
  arXiv  Detail & Related papers  (2023-05-30T13:51:49Z)
• Observation of Exceptional Points in Thermal Atomic Ensembles [8.775696647310692]
  Exceptional points (EPs) in non-Hermitian systems have spawned intriguing prospects for enhanced sensing. We experimentally observe EPs in multi-level thermal atomic ensembles, and realize enhanced sensing of magnetic field for one order of magnitude.
  arXiv  Detail & Related papers  (2023-04-14T08:14:16Z)
• Tunneling Gravimetry [58.80169804428422]
  We examine the prospects of utilizing matter-wave Fabry-P'erot interferometers for enhanced inertial sensing applications. Our study explores such tunneling-based sensors for the measurement of accelerations in two configurations.
  arXiv  Detail & Related papers  (2022-05-19T09:22:11Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.